Originally Posted by
circlemaker
if being fast and competitive (informally) is important, should I buy a light weigh, or aero version of a Canyon or comparable road bike?
As already noted, aero almost always provides more gains than reducing weight.
However, the gains that you'll get by using a new aero bike vs a new endurance, all-road or gravel bike (assuming the same riding position and same tires) are likely to be small, probably 5-10 watts. That matters if you are sprinting for the win in a Cat3 race. That doesn't matter at all if all you want to do is pass people on your daily rides.
You should also be aware that today, road cyclists run wider tires at lower pressures than they did just 5 years ago.
If I needed a new bike today, I'd get an all-road type gravel bike, and set it up with slicks and a semi-aggressive position. They're a bit more versatile than aero road bikes. For Canyon that's the Endurace or Grail. Thankfully I don't need a new bike, as they're pretty spendy these days....